1. Field of the Invention
The present invention relates generally to an obstruction sensing system for an automotive vehicle and more particularly to a rearward obstruction sensing system which can detect any obstructions existing within dead angles from the driver in order that the driver can safely back-up his vehicle into a garage, for instance.
2. Description of the Prior Art
Various obstruction sensing systems for automotive vehicles are well know. In these systems, a plurality of pairs of transmitter and receiver are arranged at the corners of the vehicle body in order to define each warning area near the vehicle. In the case of a rearward obstruction sensing system, usually one transmitter and receiver pair is arranged at each of the four corners, i.e., at the front left and right as well as the rear left and right portions of the body. When the system detects the presence of any obstructions within the predetermined warning areas, the alarm sound is produced and the warning area and the obstruction distance are both indicated on a zone display device pictorially.
When backing up a vehicle, the driver usually turns his face to the rear side of the vehicle, whereby this zone display device is usually disposed on the rear parcel rack. Therefore, when the driver hears the alarm sound, he must watch the zone display device in order to determine the direction of the obstructions and the distance from the vehicle to the detected obstruction. This causes a problem in that the driver cannot concentrate his attention to the backward side of the vehicle; in other words, the driver cannot intuitively or sensorially recognize the direction and distance of obstructions.
A more detailed description of the prior-art rearward obstruction sensing system for an automotive vehicle is made with reference to the attached drawings under DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS.